I am so glad the negative comments stopped and encouragement followed. Let me tell you a story.
I started camping life in a tent like most everyone else here did. I eventually moved up to a tiny tiny little FAME camper. This worked for a summer but I really didn't like it because it was too cramped.
The next spring I found a fairly nice 30' Coachman bumper tow that seemed to be the answer. I made the deal and dragged it home. It was about 15 years old but had good tires and was huge compared to my old 14 footer. On my first night in the camper a few weeks later I kept hearing a noise below the bed and in the wall like a branch rubbing the side. It was dark and I took it as being just that. In the morning I woke up to find ants had invaded my dry foods and was pretty grossed out but then realized they were making a trail to the bedroom. It was just an overnight trip so I headed home and didnt put two and two together right then.
Two weeks later I was in the camper cleaning and randomly stepping on a few ants and decided to spray. I lifted the bed and sprayed ant killer under it and the walls. There was a bit more noise and then ants everywhere. I ran. (Quite manly response right??) I went to hardware and bought 5 Bug Bombs and set them off inside and in the 2 compartments and athe following weekend started opening things up. My entire real wall was a giant ants nest as was the last 8 feet of the floor including the entire bedroom. It was bad. I had taken a small loan to buy it. I had a year just to pay it off. Fixing was my only option. Here is what I learned:
Anything can be fixed with a little knowledge and basic skills. Before you even invest another penny, take it to someone who knows TRAILERS but preferably not an RV place. THis is YOUR project. Have a trailer guy take a look at the frame and carriage and brakes and axles etc to be sure they are road safe. If it is you are safe to play.
Many campers and RVs are built by laying out a deck complete with cabinets and furniture and flooring and then setting the walls down around it. You need to reverse this to the degree you can. I started by removing all furniture, beds, partitiions etc to get the unit as empty as I could.
Next I removed the wall covering which back then was thin paneling. With that came the insulation which was very very minimal. I left the outside skin on a majority of the camper. I only removed what I absolutely had to where the wood was badly damaged.
Next came the floor coverings. I had vinyl flooring in halls and carpet in the bedroom. This had all been installed before the interior OR the exterior walls. I simply cut around the base of all the walls and exposed as much floor as I could so that the 3/4" plywood flooring could be removed.
Once I had taken about 100 pictures of everything and at least 100 measurements I started tearing out the bad stuff. I too had a door in the middle of the worst of the damage. Someone put it in there so you can slowly figure out how and remove it the same way. If you are very careful it can be saved and reused. I will admit here that the door never quite shut as nice as it originally did but in an emergency would be an escape. We just didn't use it much after that. It shut and latched etc but was a little sticky.
Once the bad is out you can start rebuilding. I recommend tearing out and fixing a section at a time. Fresher memories are always best.
The only other cautions would be to watch carefully for wires and hoses. Both can be buried in the bad wood and wires are easy to cut and not even notice. I cut a small ground wire for water pump and never noticed. I had to bite my lip and get someone who knew what they were doing to tell me why the pump wouldnt go.
Now get out there and have FUN!! If tempers start getting short and it stops being fun STOP!!!!! That is a good time to go get wings and a beer and walk away until next weekend. Also...Take breaks from the project for a day or a week now and then. A Project of fun and love can turn into a ball and chain if you try too hard too fast.